In case a vehicle body to which wheels are already mounted (hereinafter referred to as a “vehicle”) is conveyed by a trolley conveyor in an automobile assembly line, the body of the vehicle is usually hanged by a hanger for conveyance, and for transferring the same onto a slat conveyor a vertically movable apparatus for transferring vehicles that receives vehicles from the hanger by supporting the wheels instead of the body of the vehicles is used. For such an apparatus for transferring vehicles onto a conveyor, a pair of front and rear wheel supporting arms that freely open and close in a horizontal manner between a closed posture for supporting the wheels at a predetermined position in terms of the convey direction and an opened posture for releasing the wheels to the convey direction are used as a wheel supporting means. However, for such a conventional apparatus for transferring vehicles onto a conveyor, both the front wheel supporting means supporting front wheels of the vehicle and the rear wheel supporting means supporting rear wheels of the vehicle are constituted of a pair of front and rear wheel supporting arms that freely open and close, as described in Japanese Patent Application No. 2007-18647.    Non Patent Citation 1: Japanese Patent Application No. 2007-018647